Warp stop motion for looms



p 16, T. A. B. CARVER 1,775,887

WARP STOP MOTION FOR LOOMS Filed Jul 14. 1928 Patented Sept. 16, 1930 UNITED STATES PATENT OFFICE THOMAS ALBERT BRIGGS CARVER, OF CHEA'J'LE HULME, ENGLAND, ASSIGNOR T0 CARVER TEXTILE PATENTS LIMITED, 03? MANCHESTER, ENGLAND, A BRITISH COM- IPANY My invention relates to mechanism wherein the movement of an element closes an elec- 'tric circuit to knock oft a starting lever for thepurpose of stopping the mechanism, and

5 is applicable to, and will be described as applied to weaving looms having that type ozt warp-stop motion in which the desired stoppage of the loom on the breakage of a warp thread is efiected electrically, through the inaction of detectors which engage with the warp threads and which on the breakage of a thread close a circuit through a knock off motion to stop the loom. The particular object of the invention is the provision of a 15 knock oii motion which itself supplies a suflicient force to throw oii the starting and stopping handle without assistance from a moving part of the loom, and which can be actuated from the source of supply at any ordinar VOltZI 'B and throu h the s stem of wiring which may be already installed in the mill in which the loom is situated, for any purpose such as lighting or power.

According to the invention I provide a 95 spring which when unconstrained will maintain the loom handle or lever in the oil or stopped position, and I ttlSOxPIOVlClG a magnetic field which normally constrains the said spring when the handle is moved to start the loom, with means for neutralizingthe effect of the said magnetic field when a warp thread breaks.

By this combination of spring and neutralizable magnetic field a very strong, rapid and certain oft movement of the loom handle, immediately on a warp thread breaking, is assured, the whole apparatus being self-containedl To provide the magnetic field an electromagnet is fitted in such a position that it will through desired intermediate members maintain the spring in its constrained position by means of a winding on the said magnet which winding is in an electric circuit normally closed. 011 the electromagnet may be a further winding opposed to the first, that is to say, wound in the opposite direction, this opposed winding being included in a circuit which is normally open, and closable by movement of a warp thread detector. Thus,

Application filed July 14, 1928, Serial No. 292,887, and in Great Britain July 23, 1927.

when a warp thread breaks, constraint is removed trom the spring by the neutralizing act-ion ot' the opposed winding on the magnetic field.

in order to avoid passing a high voltage through the warp thread detector system vith consequent danger from sparking, a make and break device employing only a low voltage may be utilized to close the opposed winding circuit when a warp thread breaks. A suitable make and break device may consist of an armature which is normally held away from a contact, this armature and contact being in the opposed winding circuit, and a magnet which maintains the armature in this position by a inding in a low voltage circuit. On the magnet thus arranged a further opposed winding may be put, the warp thread detector system being in the same circuit as this opposed winding. On a detector closing this circuit therefore, when a thread breaks, the armature is no longer held by the magnet and is released to make contact with the contact member and close the main opposed winding circuit to remove constraint from the loom handle spring. 7

The invention will now be fully described with reference to the annexed diagrannnatic drawing, which shows a convenient arrangement oi loom handle, spring and magnetic field, and circuits for the electro-inagnet and for the make and break device as above referred to. No part of the loom itself is shown other than the loom handle.

Referring to this drawing, the loom handle is shown at A. and when this handle passes into and out oi the notch B, thus being held in the on position, it presses against a head 1 secured to a plunger which is slidably fitted in fixed guides C. Surrounding the plunger 2 is a strong spring 3 abutting at one er:- tremity against one of the fixed guides C and at the other extremity against a collar 45 pinned on the plunger .2. When unconstrained therefore the spring 3 will press the loom handle A into the off position through plunger 2 and head 1.

On the end of the plunger 2 is formed or secured an armature 5 which, when the loom handle A and thus the plunger 2v are forced m9 into the on? position seen int-he drai'ving enters a magnetic field of an electro-magnet 6' and is held close to the poles of the said magnet. The magnet is Wound With two Wind ings, one of Which K is the GHGLglZ lDg WiIICl ing and is in circuit with a source ofcurrent suppl'yS the circuit, as shown'inthe drawlngbelng permanently closedunless opened ,Wl16IL-tl16 l0OHl is not Working-the other .ly o pen, and clojsable onfbreakage' of'a Warp WindingJ being in a circuit which is normal- '7 thread as hereinafter more fully referredto.

- The armature 5 is therefore normally held against thepoles v ot the magnet 6; during the Work ng ofthe loom, to constrainthe spring I :3,-aEnd -'When a Warp-threadbreaks and closes the circuit in WliiCh'lS included the coil 5, the effect on armature 5--is neutralized and the spring 3 forcibly and rapidly knoclrs otl th'e 'h a'ndle A i f x:

Asthe passing of the necessarily strong current, required by: Xvinding J, through the detector electric circuit might cause danger *fIOIii sparking the make and break system -Wl1lCl1 dra vsits current from the common :source S. V'Qn theimagnet 9i is' an opposed Winding 11, which isincluded'i'n circuit which also in'cludes: the detectors, indicated byVX- on the drawing; Normally therefore the armature Land ,the contact 8,, are sepia rated, but on the detector circuit closing movement the Winding llineutrelizes therpull of the magnet 9 onarin'ature 1') and the latterlnoves a ainst the contact'8, thus closin the V 3 1 V b circuit in hichis included the neutralizing Winding J ofthe eleetro-magnet 6; I l

-Equ'ivalents may be employed instead or; themake and hr aksystem just described.

w Forinstance the armature L may'h'e'nornially.

I her 8, on thefwarp detect in the position shown iii-the drm ingand he drawn to make contactwth the contact.ine1nor circuit being closed X, by an elect-rounagnet, energized only on a-Warp thread breaking. The device shown and described above is "however ce tain simple in 'it sfactioni T I claim 5 1.- ln mechanismwherein apga'p 'is vadapted mechanisids'toppiiigjposition,- a magne'tie :tob Q 9Sed 12076 93 a Si P: motion electric cir-' cu1t,ma"start1ng lever,' a spring which when unconstrained forceslthe starting lever into field'which normally constrains the spring whentheflstarting leverhas been moved to-its operative position, and mea s for neutralii ing?theniajgneticfieldand thus itslefiect on i-ng Winding;

. l mes? the spring, as a result of'the closingof they" stop motion circuit.- T r V 2. In mechanism wherein a gap is adapted to beclosed to close a st-op mot-ion electric circuit, a starting lever, a spring which When unconstrained forces the sta'rtin lever into n1echanism1+stopping position, an armature on the starting lever, a magnet and energiz ing WVlllCllJlgdlllGI'GOl'l forming a magnetic ffield for the armature, and ffa ,f'urtherand v opposedW nding on: the magnet winch op-' posed Winding is energized by the closingof the stop motion circui v p 3. Inineehanism wherein a gapis adapted to be closed to close a stop motion electric circuit,a starting'lever, Vii-spring! Which when unconstrained forces the starting lever into mechan smstopping positron, anarmature on the starting lever, a-ma gnet and ener ggiz ing Winding vthereon :forminga magnetic field forthe armature, afurtherand opposed Winding'on the niagnetand included in a sep arate c1 rcuit" to that of the first Winding,

a second magnet h av'ingslow voltage energizifield' of such second-magnet, such armature ma] ntaming open the circuit Wh-i'cli includes an armaturev in the magnetic the opposedinding!oftlieifirst,magnet, and 1 means for neutralizing the low: voltage magnetic field by tlie closingoflithe stop ni otion to he closed to close'iaistopi motion electric circuit, aistartinglever, a spr ngxvvhich when unconstrained forces .thestarting lever into 1' :mechanisrn-stopping position, an, armature on the starting-lever, irig Winding .thereon V fiel (,l foi; the armature, a a Winding? on the magnet .an

magnet andenergi'z i 'ormin-ge a magnet1c field of such secondiiriaghehysucli armature maintaining" open. the circuit: which includes irther; and-opposed 7 d. included ina separate circuit tothatof the firstf winding, V a: secondfniagnet having a low'iloltageener-f g'iZingwincling-an armatureinithe-magnetio" A y 4'. In mechanism whereinagapTis-adapted 7 the opposed windingof the tirst m'a net, and g further loW voltage winding oii the second magnet, opposedto the energizing 'Winding thereon and includedinthe stop 1notio1i3cir-- "In testimony WhereoijI haveliereunto set inyhandlf Teen AS ALBERT hide CARVER 

